Conversion from Resurfacing to Total Hip Arthroplasty

In recent years, resurfacing arthroplasty for the hip has become possible. Hip resurfacing arthroplasty is a type of hip replacement that replaces the arthritic surface of the joint but removes far less bone than the traditional total hip replacement.

The advantage of hip resurfacing is that by removing less bone it is possible to do a total hip replacement (THR) later. But surgeons are wondering if this type of revision is really possible? How often does it happen? There haven't been any studies on this conversion since 1980. And many things about the devices and the procedures have changed since then.

In this study, surgeons at the Joint Replacement Institute in Los Angeles, California review a group of 20 adults who had the resurfacing procedure (the study group). All patients with resurfacing arthroplasty received the same metal-on-metal implant. The femoral head portion was cemented in place for all patients. The stem was only cemented in about 40 per cent of the cases.

They compared the results with a similar group of patients who had a THR (the control group). Pain, walking, function, and activity were used as the measures of results. X-rays were also reviewed for both groups.

They found no differences between the groups. Outcome measures were the same. Operative time, blood loss, and bone loss were also equal between the two groups. The number of complications was the same between the two groups.

The authors conclude that the proposed advantage of resurfacing arthroplasty (easy revisability) is real. Successful conversion to a THR is possible. They suggest a larger study needs to be done to confirm these findings. Longer follow-up time is also advised.



References: Scott T. Ball, et al. Early Results of Conversion of a Failed Femoral Component in Hip Resurfacing Arthroplasty. In Journal of Bone and Joint Surgery. April 2007. Vol. 89-A. No. 4. Pp. 735-741.